Posts tagged: Zero-Day Vulnerability

A new Java 0-day vulnerability has been discovered, and is already being exploited in the wild. Currently, disabling the plugin is the only way to protect your computer.

Description:
The MBeanInstantiator in Oracle Java Runtime Environment (JRE) 1.7 in Java 7 Update 10 and earlier allows remote attackers to execute arbitrary code via vectors related to unspecified classes that allow access to the class loader, as exploited in the wild in January 2013, as demonstrated by Blackhole and Nuclear Pack, and a different vulnerability than CVE-2012-4681.

Impact:
By convincing a user to visit a specially crafted HTML document, a remote attacker may be able to execute arbitrary code on a vulnerable system.

This actual vulnerability was later confirmed by security firm AlienVault Labs. With Kafeine’s help, the company reproduced the exploit on a new, fully-patched installation of Java, and used a malicious Java applet to remotely execute the Calculator application on Windows XP as shown in the below screen-shot:

An unpatched Windows vulnerability considered a critical threat by security experts is being exploited by cybercriminals.

Microsoft disclosed the flaw in XML Core Services (MSXML) 3.0, 4.0 and 6.0 June 12 during its monthly release of patches. The security advisory, which was separate from the patch release, offered a workaround for vulnerability CVE-2012-1889, but no fix.

Vulnerability CVE-2012-1889 is simple to exploit in all known versions of Internet Explorer. An attacker can make a CLSID-identification request by calling MSXML library methods and create an object identifier in order to try to access a non-existent object. Proof of Concept code for causing a crash looks like this:

This code looks simple, but generates memory corruption and crashes Internet Explorer. The exploitation code tries to request a non-initialized object, but reference to memory region already exists. Memory corruption takes place in the helper function _dispatchImpl :: InvokeHelper() in the MSXML library.

Currently, this vulnerability has no patch available but Microsoft has released a Fix it solution. We strongly suggest that you consider this workaround – for now.